NEW: add duration to the results data frame
NEW: add duration to the results data frame

Former-commit-id: 1549fd34f6c89ffc04b5c581f42ab13b35d790ce
Former-commit-id: 853c505d77f9db025ae6333a48ff16e6668eea89
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox